1. Field of the Invention
This invention relates generally to the field of food service, food preparation, and food preservation, and, more specifically to apparatus for heating catered food items utilizing a butane heat source and a burner control mechanism.
2. Description of the Related Art
While chafing dishes have been used in a variety of settings and for heating a wide variety of food items, there are limitations in existing chafing dish technology, including such things as the inability to maintain sufficient heat to insure food safety, the inability to heat food in the chafing dish uniformly, the inability to heat food reliably outdoors' under breezy conditions (when using sterno) or due to the absence of electricity (when using heating rods), and the inability to heat water in the water pan quickly.
Portable gas stoves have been used for such things as camp cooking. The present invention chafing dish was designed to utilize the benefits of such stoves, that is, a powerful, non-electric heat source that could be regulated effectively to 1) increase efficiency. 2) increase food safety, 3) promote uniformity of temperature to enhance flavor, and 4) increase suitability for outdoor use. Thus, butane gas burners were selected as the heat source for an improved chafing dish technology. The design of the present invention chafing dish incorporates a butane gas burner into the base of a chafing dish. The burner utilizes gas from small, commercially available cans of butane gas. After a safety device has been engaged, the valve of the gas can is opened with an initiating pin and gas in the gas can is then led through a regulator and into the integrated burner via a copper tube. The present invention chafing dish has a device that regulates the rate of flow of the gas, thereby allowing improved temperature control. The present invention also utilizes an electronic ignition to ignite the gas at the burner for easy use.
Chafing dishes have been used to heat food for many years. Chafing dishes utilize a portable heat source to heat water in a pan or tray (hereafter referred to as the “water pan” or “water tray”;): the heated water in the water pan in turn heats food in a second, separate pan or tray (hereafter referred to as the “food pan” or “food tray”) placed into the water pan. The chafing dish is used in locations such as buffet tables, where no fixed heating or cooking source (like a stove or range) is available.
Prior chafing dish technology employed one of three heat sources to heat the water ir the water pan: 1) sterno cans placed below the water pan. 2) electric heating rods placed in the water pan, or 3) a wick-type fuel called a “heat source” that functioned essentially like sterno.
Earlier chafing dish technology using sterno cans placed under the water pan is deficient for a number of reasons. First, the heat generated by burning sterno cans is not reliably consistent. Flood temperature throughout the food pan may rise and fall due to this inconsistency. Also, temperatures in different areas of the food pan may vary. These conditions can cause at least two significant problems: a) potential food safety problems if foods are not kept at minimum temperatures required to prevent microbial contamination, and b) adverse consequences to the flavor of the foods being heated in the chafing dish as food gets too hot or too cold. The inventors' design utilizes a heat source that greatly increases the consistency of heat delivered to the food tray and uniformity of heat distribution throughout the area of the food tray, thereby diminishing the risk of these problems.
Second, the heat generated by burning Sterno cans is not efficient. Chafing dishes utilizing sterno cans requires considerable more time to heat the water in the water pan than does the present invention chafing dish described herein. The present invention chafing dish heats the water in the water pan to one hundred forty degrees Fahrenheit, the temperature required by food safety regulations in the inventors' home state, in approximately four minutes, whereas existing technology utilizing sterno or electric rods require between twenty-five and forty minutes to reach this temperature. Moreover, because the heat source is more reliable, the invention enhances efficiency for the user by eliminating the need for frequent visual inspections to determine whether the heat source is functioning. In addition, sterno cans; are inefficient because the temperature cannot easily be changed or regulated, with the method for changing temperature using sterno being to partially cover/uncover the can manually with a lid thereby allowing less or more heat to be released. This is both difficult, and potentially dangerous. The present invention design allows for easy and safe temperature change and regulation by means of an easily accessible control mechanism built into the front of the chafing dish. Finally, the present invention increases efficiency and diminishes environmental contaminants because unused butane can be stored and utilized at a later date, whereas unused sterno must be discarded because it cannot be transported or stored safely once opened. Third, the heat generated by burning sterno cans is not reliable outdoors, where many events requiring catered food items take place. The flame generated by the sterno can be easily extinguished by moderate breezes, and, even when not fully extinguished, sterno flames waiver greatly in such breezes. The present invention has been outdoors and performs significantly better in windy conditions than prior art chafing dishes using sterno.
Chafing dishes that use an electric rod to heat the water in the water pan suffer from some of the same deficiencies noted or sterno use, such as slow heating time, uneven heat, and limited usefulness in area (both indoors and outdoors) where there is no convenient or safe electric socket. As noted above, the present invention incorporates means to minimize or eliminate these shortcomings.
Two portable butane burners are known that can be used with prior art chafing dishes to replace the sterno, wick-type heat sources, and electric rods. However, neither has all of the advantages of the present invention. One such invention is the butane burner assembly disclosed in U.S. Pat. No. 4,899,722 to Horewitch (1990). It discloses a butane housing similar to that of the present invention, with a burner secured within the top surface of a cantilevered arm extending perpendicularly thereto from the side remote from its pivoting door. Thus, the Horewitch burner can be placed under one end of a water pan supported by its upper frame. With the butane can housing positioned in part beneath the water pan. The Horewitch housing also has adjustable legs, that are used to adjust the distance between its burner and the bottom of the water pan. Set up for a series of Horewitch inventions in a catered food line would take considerable more time than that required for the present invention chafing dish unit of the present invention. Thus, instead of having to position a prior art chafing dish, ad just the eight feet on two Horewitch burners, and then position the cantilevered arms of each Horewitch burner under a different end of the water pan in a prior art chafing dish, present invention set up only requires positioning on a serving surface. The present invention also has a space-solving advantage over the Horewitch invention, and will allow the closer spacing of elevated chafing dish water pans where needed. The second such invention is the butane burner assembly disclosed in U.S. Pat. No. 5,211,157 to Schwartz (1993), which discloses a butane housing similar to that of the present invention. However, the Schwartz burner has a handle and an annular flange that are used for positioning it under a surface needing to be warmed. When used with a chafing dish having openings below the water pan for sterno or wick-type heat sources, the Schwartz flange allows its burner to be set secured within such an opening. Since a piezo-electric ignition line and a fuel supply line are connected between the Schwartz burner and its butane can housing, as shown in FIG. 1, it has removable connections at the butane can housing so that the ignition and fuel lines attached through the bottom portion of the Schwartz burner can be temporarily detached for extension through the chafing dish opening prior to setting the Schwartz burner in place. Thus, the present invention also has a time-saving advantage over the Schwartz invention, and instead of having to position a prior art chafing dish, disconnect the ignition and fuel lines attached to the Schwartz burner from the butane can housing, extend the lines through a sterno or wick-type heat source opening in the bottom of the chafing, dish, using the handle attached to the Schwartz burner position the Schwartz burner within the selected sterno or wick-type heat source opening, and then reconnect the ignition and fuel lines to the butane can housing, present invention set up only requires positioning on a serving surface. Additional time savings would also be realized by the present invention when food service is complete, as there would be removal and storage of only one item, and no dismantling time involved. With the Schwartz and Horewitch inventions a person must move two or more items when dismantling each such invention, with the Schwartz invention taking even longer to remove the ignition and fuel supply lines from the Sterno or wick-type heat source opening. Also, the integrated burner in the present invention is simpler in design and eliminates extra components needed in the Horewitch and Schwartz inventions, such as the cantilevered arm, quick disconnect lines, flange, and handle. Thus, the present invention also has cost advantages over the Horewitch and Schwartz inventions.